_____13. In the analysis of variance with three groups the null hypothesis is

a. The three population means are all different.

b. At least one of the population means is different from the others.

c. The three population means are equal to each other.

d. We can't tell from what is given here.

_____14.In the analysis of variance, the more the null hypothesis is false,

a. The larger the value of F.

b. The smaller the value of F.

c. The smaller the value of the correlation coefficient.

d. The harder it is to find a significant difference.

_____15. If you obtain a significant F-statistic then you know that:

a.at least one of the means is significantly different from at least one other mean

b.all of the means are significantly different from one another

c.all of the means belong to the same population

d.the null hypothesis is probably correct

_____16.What is the critical value of a two-tailed one sample t-test, a = .01, n = 25?

a.1.708

b.2.064

c.2.787

d.2.797